Louisiana warns beachgoers amid surge in flesh-eating bacteria infections

State confirms nine cases, including five deaths, from Vibrio vulnificus organism, which thrives in seawater

Health officials in Louisiana are urging beachgoers to take precautions during a summertime surge in infections from a flesh-eating bacterium found in coastal waters.

Louisiana has confirmed nine cases of Vibrio vulnificus infections this year, the state’s health department said last week in a news release. All were hospitalized, and five died. During the same period over the previous decade, Louisiana reported an average of seven cases and one death.

“Seek medical care immediately if a wound exposed to brackish or salt water becomes red, swollen, painful, warm or discolored,” officials said in the release.

Vibrio bacteria thrive in seawater and in the brackish mix of fresh and saltwater found in estuaries and lagoons. Most infections are reported from May to October, and most happen in states along the Gulf coast. Doctors say the Gulf is an ideal environment with the right amounts of salt and heat to let this organism proliferate.

The mostly deadly type is Vibrio vulnificus , according to the Centers for Disease Control and Prevention (CDC). As many as one in five of those infections are fatal, a much higher rate than other types of Vibrio bacteria.

The rate of infections remain exceptionally rare compared with other infectious diseases. But once the bacterium enters the body it can cause bruising, swelling and decay within hours and bring on septic shock and death unless there is rapid treatment with powerful antibiotics.

Last year Louisiana recorded five deaths from the bacterium among at least 26 people who were infected, all of whom were hospitalized. One of those who died, Basil Kennedy, 77, became sick after he scraped his leg on a boat trailer then entered the water; he died three days later.

Florida has reported 14 Vibrio vulnificus cases and two deaths so far this year, compared with 33 cases and five deaths for all of last year.

Some people become infected by eating raw or undercooked shellfish – particularly oysters. But a large percentage fall ill when the person is in ocean or brackish water and the bacteria enter the body through small breaks in the skin.

Doctors say severe cases are seen more often in elderly patients, people with weakened immune systems, and those with liver disease, diabetes and certain chronic illnesses.

Scientists say the climate crisis is helping the germs proliferate and spread northward. As the oceans warm, the concentration of Vibrio in seawater also rises, increasing the risk of infection.

A 2023 study found that the northernmost case has been shifting by about 30 miles each year, and that cases overall have been rising, and over time the northward proliferation might bring infections within range of population centers around New York.

Vibrio vulnificus can enter the body through unhealed cuts and scrapes, recent piercings and tattoos, and recent surgical incisions. People should immediately wash cuts and scrapes thoroughly with soap and clean running water after coming in contact with coastal waters or raw seafood, the CDC said.

The Associated Press contributed reporting